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In recent years, with the increasingly serious environmental pollution and energy crisis, bio-diesel, because of its renewable, biodegradable and non-toxic side effects have been more and more attention. Currently, the main source of biodiesel feedstock oil is animal and vegetable fats, as well as catering waste oil, the presence of the high cost of collection and transportation difficulties, therefore looking for an inexpensive raw materials has become the key to the industrialization of bio-diesel. The studies have shown that some microorganisms can accumulate in the body fat, such as yeast, bacteria, mold, and microalgae. With the rapid development of the biodiesel industry, the microbial oil fuel sources will become rich potential of the biodiesel industry. Sudan black b stain from the laboratory marine yeast library 771 marine yeast screened seven higher fat content of the yeast to Soxhlet extraction rescreening get a higher oil production in the marine yeast strains TJY15a, the strains isolated from the surface waters near the Dagang District of Tianjin, China. Through traditional yeast species identification and molecular biological identification, the final identification of the marine yeast strains belonging to the plastic red yeast (Rhodotorula mucilaginosa). Single factor method using glucose as a carbon source, strain fermentation to TJY15a the lipid production medium and culture conditions to optimize the optimal lipid production medium components (w / v): 6.0% of glucose sugar, yeast powder 0.86 % (N ratio of 70), KH2PO40.7%, Na2HPO4 0.25%, MgSO4 · 7H2O 0.15%, CaCl20.015% FeCl3 · 6H2O 0.015%, ZnSO4 · 7H2O 0.002% of MnSO4 · H2O 0.006% (NH4 ) 2SO40.05%, the initial pH of 6. Optimal culture conditions: shaking culture for 72 h at 28 ° C and 180 rpm. Cultured under the best conditions, the strains TJY15a grease maximum yield can reach 49.6%, biomass yield reached 17.9 g / L this experiment cassava starch as a cheap carbon source, the use of the marine glue red yeast strains TJY15a transformed cassava starch hydrolyzate supplemented with enzymes and starch production yeast oil after the oil-producing conditions optimization and fermentation process experiments, the final oil production up to 52.9%, the biomass yield of 21.8 g / L. Lipid production TJY15a strains subjected to gas chromatographic fat component measured obtaining 85.8% C16: 0 and C18: 1, in particular C18: 1, about 63.5%, indicating that is a long-chain fatty acid composition, so TJY15a obtained grease can be used as a good fuel supply to be used in the synthesis of biodiesel. In this paper, glue red the yeast TJY15a in 2L fermenter fermentation characteristics. The results show that: After the fermentation 148 h complement plus two carbon source, in a 2L fermenter TJY15a strain cell biomass up to 24.0 g / L, the oil production of up to 52.5%.
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